Foundry flask



R. J. HINES FOUNDRY FLASK Dec. 8, 1959 2 Sheets-Sheet 1 Filed June 28, 1957 INVENTOR. Russau. J.H|'Nes BY M\/Mn 7 ATTORNEYS Dec. 8, 1959 Filed June 28, 1957 Sheets-Sheet 2 5 5 1 J I l w;

INVENTOR. Russau. J.Him=.s

ATTORNEYS United States Patent FOUNDRY FLASK Russell J. Hines, Lakewood, Ohio, assignor to The Hines Flask Company, Cleveland, Ohio, a corporation of Ohio Application June 28, 1957, Serial No. 668,797

2. Claims. (Cl. 22-107) This invention relates to a separable foundry flask of the type having side and end walls interconnected at abutting ends to form a closed boundary for containing sand, and more particularly to an improved means for retaining an endless band member within the flask whenever the same is in locked position.

In one of the methods used for making metal castings, a pattern plate is placed on the bed plate of a press, the plate having the cope-forming portion of a pattern on the upper side thereof. A conventional foundry flask is then placed'on the pattern plate in aligned relationship therewith. The flask may be rectangular in configuration and it may have side and end walls having a hinged interconnection at one corner and a separable interconnection at a diagonally opposite corner to permit its subsequent removal from a sand mold formed within it. An endless band member having the same configuration as the flask is then telescoped into the flask. The band functions as a reinforcing means for the completed mold during the pouring operation. Sand is then blown into the flask under high pneumatic pressure, after which the sand and the band undergo a squeezing operation, wherein a press head (having a drag forming portion on its underside) is forced down onto the top surface of the sand until the top of the band is flush with the top of the sand and preferably is disposed slightly above the top of the flask thereby forming the mold. Thereafter, the filled flask is transferred to a pouring station and the flask is removed from the mold. The operation of flaskfilling, band inserting and the squeezing operation are repeated, whereupon a second mold section is superimposed upon the first, the flask being removed and, in the case of stack molding, the operation is repeated until a desired number of molds suitable for pouring is obtained. In each mold, the band remains imbedded within the mold after the flask is removed, and provides a reinforcement against bursting of the mold upon the introduction of molten metal thereinto.

In carrying out the foregoing method of molding, considerable difliculty has been experienced in maintaining the band in proper position with reference to the top of the flask during the molding operation, particularly since the band heretofore has been held in contact with the walls of the flask merely by frictional engagement therewith. The band is usually a strip of metal, the ends of which are welded together, hence, manufacturing tolerances, together with the tendency of the band to warp or bend during use have made the alignment of the band with reference to the flask difficult of maintenance after repeated operation. Any force exerted by the closing of the flask and operating to bend the band will result in the distortion of the sand in the mold when the flask is opened and the band springs back to its normal shape.

An object of the invention is to provide a molding flask employing a band member, wherein destruction of molds formed therein and caused by the inadvertent flexing of the band walls during the mold making operation is prevented.

Another object of the invention is to provide a molding flask using an endless band member, wherein the band is engaged and supported at middle portions of the side and end walls thereof, whereby uniform engagement between the flask and band is regularly assured, during the mold making operation.

Briefly, the foregoing objects are accomplished by providing pads adjacent the upper central portions of the walls of the flask and by so positioning the pads that they engage the mid-portions of the side and end walls of the band and exert a slight pressure thereonrwhen the flask is closed. Such pressure tends to hold the walls of the band slightly inwardly, so that upon release of the flask the band walls tend to resume their normal shape without distorting the sand.

Other objects and advantages of the invention will become apparent from the following description taken in conjunction with the accompanying drawings in which:

Fig. l is a perspective View of a molding flask made in accordance with the invention and showing the band member positioned within the flask;

Fig. 2 is a top sectional view taken along the line 22 of Fig. l; I

Fig. 3 is a view similar to Fig. 2, but showing the flask lock mechanisms in released position;

Fig. 4 is a perspective view of the band member;

Fig. 5 is a side-elevational fragmentary view taken along the line 5-5 of Fig. 3.

Referring to Figs. 1 and 2, there is shown a flask F, which comprises the side walls 10 and 11 and end walls 12 and 13, disposed in abutting end-to-end relation to form a rectangular frame which is open at the top and bottom and is adapted for receiving a mold making material such as sand therein. The walls may be releasably interconnected at two diagonally opposite corners by the lock or latch mechanisms 15 and 16 (Fig. 2). However, the flask may have a hinged interconnection at one corner and a releasable lock mechanism at the diagonally opposite corner.

The flask F is adapted to receive an endless band member B in substantially tight telescopic engagement with the inner surfaces of the flask walls, as shown in Figs. 1 and 2. The band is of the same configuration as the flask and comprises the side walls 20 (Fig. 4) and 21, and end walls 22 and 23 joined in end-to-end relation to form a rectangular frame. After the sand mold is formed, the band remains imbedded within the mold and functions as a reinforcing means to prevent the mold from burst-ing during the pouring operation.

To provide a close-fitting engagement between the band and the flask during the mold-making operation, the flask is provided with pads or inserts 32, 34, 36 and 38, which may be of metal or of resilient rubber-like material and which extend downwardly from the top edge of the flask for engagement with the midportions of the walls of the band. The pads are rigidly fastened to the respective walls of the flask by any suitable means, and thus become a permanent part of the flask.

In the preferred form, the inserts 32, 34, 36 and 38 are disposed substantially at the central portion of the respective flask walls, whereby the top edges of the inserts are flush with the respective top edges of the flask walls.

To insert the band into the flask, the lock mechanisms 15 and 16 are released as shown in Fig. 3, thus opening the flask and permitting the band B to be telescoped loosely therein. After the band is thus positioned, it may be locked in such position by closing the locking mechanisms 15 and 16 as shown in Fig. 2, whereby the band is held in place within the flask solely by friction The terms and expressions which have been employed are used as terms of description, and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown or described or portions thereof, but it is recog nized that various modifications are possible within the scope of the invention claimed.

I claim:

1. In a molding flask having four vertical walls interconnected at their respective ends to define an enclosed sand boundry and having latching mechanism on at least one corner thereof to releaseably interlock the abutting ends of the adjacent walls, and wherein the opposing flask walls are contractable and expandable with respect to one another in a horizontal plane upon unlocking of said latching mechanism, said flask being adapted to receive an endless metallic band of similar plan configuration as said flask and in telescoped vertically adjustable supported relation in said flask, the combination therewith of a flat resilient pad attached to the inner face of each of said walls and adapted to frictionally engage the respective confronting side of said band to hold the latter in selected vertically telescoped position in said flask and exert a slight inward pressure on the respective side of said band upon locking of said latching mechanism, each of said pads being secured to a respective one of said walls substantially centrally thereof in a lengthwise direction, each of said pads commencing substantially at the top edge of the respective flask wall and extending downwardly toward the bottom edge thereof to provide a vertically disposed generally planar surface of substantial magnitude for frictionally holding said band in selective vertically telescoped relation in the flask, said opposing flask walls upon unlocking of said latching mechanism being expandable with respect to one another in a horizontal plane to withdraw said pads from frictional hold ing engagement with said band whereby said band is loose in said flask and may be readily removed therefrom. 2. In a molding flask in accordance with claim 1 wherein said pads are comprised of rubber material.

References Cited in the file of this patent UNITED STATES PATENTS 928,000 McHugh July 13, 1909 1,008,943 Bosset al. Nov. 14, 1911 1,120,759 Swift Dec. 15, 1914 2,060,941 Kline et al Nov. 17, 1936 2,103,677 Kline et a1. Dec. 28, 1937 2,306,275 Murray Dec. 22, 1942 2,323,455 Creech July 6, 1943 2,611,162 Ernst et al. Sept. 23, 1952 FOREIGN PATENTS 15,101 Great Britain June 30, 1913 410,337 Italy Oct. 9, 1943 

